I liked Clarkson's take on the M5. It was one of those cars that was a joy to drive in spite of the annoying tech BMW insisted on incorporating...
https://www.youtube.com/watch?v=gRwR1WH0rR8
https://www.youtube.com/watch?v=vnZVkdzXzFQ
But the most influential was Plato's review of the MkV GTI. I went and bought one on the strength of that review...
https://www.youtube.com/watch?v=kA7odlXCqMU
But the most memorable review for me, is Clarkson's take on the V12 Vantage...
https://www.youtube.com/watch?v=5Q0Svvdrx_E